Stretch wrap or stretch film is a highly elastic plastic film that is wrapped around items. The elastic recovery keeps the items tightly bound. It is frequently used to unitize pallet loads, but may also be used for bundling smaller items.
Known types of stretch film include bundling stretch film, hand stretch film, extended core stretch film, machine stretch film and static dissipative film.
Categories of stretch wrappers generally include manual (or hand) wrappers, rotary arm wrappers, semi-automatic wrappers, and automatic wrappers. Sub-categories of manual wrappers include extended core, mechanical brake, and pole wrappers. With extended core systems, an extension of the film's core serves as a handle for wrapping. This type of wrapper offers little stretch control and is hard on hands. With mechanical brake systems, a simple structure supports a film roll and a mechanical brake system provides resistance creating stretch of the film. Pole wrappers are similar to the mechanical brake systems, but the roll and brake are at the end of an extended pole. This creates an ergonomic design that eliminates the need to bend to wrap the bottoms of loads and strain to reach the tops of loads.
In rotary arm wrapper systems, the load remains still while a rotating arm turns around it, thus wrapping the load. This system is used for light loads, or for speeds which would otherwise cause the load to topple due to high rotation speeds.
Known types of semi-automatic wrappers include turntable wrappers and orbital wrappers. With turntable wrappers, the load to be wrapped sits on a turntable that spins the load relative to the film roll. The film roll is generally housed in a carriage which can move up and down a fixed “mast”. Stretch is achieved by rotating the load at a faster rate than the film is fed. With orbital wrappers, the film is housed in a carriage on a vertical ring. The load is then fed horizontally through the eye of the rotating ring, applying film to the load. A variation of the orbital stretch wrapper is a horizontal ring system, in which the load remains still while a horizontal ring is rotated around the load and moves up and down vertically relative to the load, similar to a rotary arm stretch wrapper.
Automatic wrappers are generally a variant of the semi-automatic wrapper systems. Automatic wrappers include a conveyor system to automatically load the wrapping machine, and automatic systems to apply, seal, and cut the film.
There is a continuing need for a horizontal stretch wrapping apparatus and method that does not require the use of a conveyor system, particularly where space is limited. Desirably, a product to be packaged by stretch wrapping is substantially stationary during the stretch wrapping process.